karl rove signaled there could be a major shift in his party's outlook. >> karl rove, could you imagine a republican candidate saying i'm for gay marriage? >> i could. >> the supreme court begins arguments on it, the legality and one benefit to endorsing the notion with one strategist te telling politico opening up the idea will open up donors around the country. >>> zuckerberg is forming an issues advocacy organization focusing on comprehensive immigration reform. >>> rand paul doesn't want to legalize drugs but doesn't want them to go to jail either. >> the last two presidents could have conceivably been put in jail for drug use. it would have ruined their lives. it got lucky but a lot of poor kids don't get lucky. >> pending senate bill would give judges greater flexibility to work around mandatory minimum sentences for those crimes. >>> claire mccaskill is throwing her support behind same-sex marriage saying it's the right thing to do. >>> president obama will host a seder dinner. he became the first sitting president to hold seder at the executive mansion back in 2009. >>> oscar de